fix(terminal): wrong row in TermRequest with full scrollback (#36298)

Problem:  Wrong row in TermRequest with full scrollback.
Solution: Subtract by the number of lines deleted from scrollback.
(cherry picked from commit 67832710a5)

runtime/doc/autocmd.txt

@@ -1028,7 +1028,8 @@ TermRequest			When a |:terminal| child process emits an OSC,
 				- sequence: the received sequence
 				- cursor: (1,0)-indexed, buffer-relative
 				  position of the cursor when the sequence was
-				  received
+				  received (line number may be <= 0 if the
+				  position is no longer in the buffer)
 
 				This is triggered even when inside an
 				autocommand defined without |autocmd-nested|.

runtime/lua/vim/_defaults.lua

@@ -566,7 +566,9 @@ do
     callback = function(args)
       if string.match(args.data.sequence, '^\027]133;A') then
         local lnum = args.data.cursor[1] ---@type integer
-        vim.api.nvim_buf_set_extmark(args.buf, nvim_terminal_prompt_ns, lnum - 1, 0, {})
+        if lnum >= 1 then
+          vim.api.nvim_buf_set_extmark(args.buf, nvim_terminal_prompt_ns, lnum - 1, 0, {})
+        end
       end
     end,
   })

src/nvim/terminal.c

@@ -149,6 +149,7 @@ struct terminal {
   // it actually points to entries that are no longer in sb_buffer (because the
   // window height has increased) and must be deleted from the terminal buffer
   int sb_pending;
+  size_t sb_deleted;                // Lines deleted from sb_buffer.
 
   char *title;     // VTermStringFragment buffer
   size_t title_len;    // number of rows pushed to sb_buffer
@@ -221,6 +222,7 @@ static void emit_termrequest(void **argv)
   StringBuilder *pending_send = argv[3];
   int row = (int)(intptr_t)argv[4];
   int col = (int)(intptr_t)argv[5];
+  size_t sb_deleted = (size_t)(intptr_t)argv[6];
 
   if (term->sb_pending > 0) {
     // Don't emit the event while there is pending scrollback because we need
@@ -228,14 +230,15 @@ static void emit_termrequest(void **argv)
     // the event onto the pending queue where it will be executed after the
     // terminal is refreshed and the pending scrollback is cleared.
     multiqueue_put(term->pending.events, emit_termrequest, term, sequence, (void *)sequence_length,
-                   pending_send, (void *)(intptr_t)row, (void *)(intptr_t)col);
+                   pending_send, (void *)(intptr_t)row, (void *)(intptr_t)col,
+                   (void *)(intptr_t)sb_deleted);
     return;
   }
 
   set_vim_var_string(VV_TERMREQUEST, sequence, (ptrdiff_t)sequence_length);
 
   MAXSIZE_TEMP_ARRAY(cursor, 2);
-  ADD_C(cursor, INTEGER_OBJ(row));
+  ADD_C(cursor, INTEGER_OBJ(row - (int64_t)(term->sb_deleted - sb_deleted)));
   ADD_C(cursor, INTEGER_OBJ(col));
 
   MAXSIZE_TEMP_DICT(data, 2);
@@ -269,7 +272,8 @@ static void schedule_termrequest(Terminal *term)
   multiqueue_put(main_loop.events, emit_termrequest, term,
                  xmemdup(term->termrequest_buffer.items, term->termrequest_buffer.size),
                  (void *)(intptr_t)term->termrequest_buffer.size, term->pending.send,
-                 (void *)(intptr_t)line, (void *)(intptr_t)term->cursor.col);
+                 (void *)(intptr_t)line, (void *)(intptr_t)term->cursor.col,
+                 (void *)(intptr_t)term->sb_deleted);
 }
 
 static int parse_osc8(const char *str, int *attr)
@@ -1372,6 +1376,7 @@ static int term_sb_push(int cols, const VTermScreenCell *cells, void *data)
     } else {
       xfree(term->sb_buffer[term->sb_current - 1]);
     }
+    term->sb_deleted++;
 
     // Make room at the start by shifting to the right.
     memmove(term->sb_buffer + 1, term->sb_buffer,

test/functional/terminal/buffer_spec.lua

@@ -473,6 +473,83 @@ describe(':terminal buffer', function()
         {5:-- TERMINAL --}                                    |
       ]])
       eq({ 22, 6 }, exec_lua('return _G.cursor'))
+
+      api.nvim_chan_send(term, '\nHello\027]133;D\027\\\nworld!\n')
+      screen:expect([[
+        >                                                 |*4
+        Hello                                             |
+        world!                                            |
+        Hello                                             |
+        world!                                            |
+        ^                                                  |
+        {5:-- TERMINAL --}                                    |
+      ]])
+      eq({ 23, 5 }, exec_lua('return _G.cursor'))
+
+      api.nvim_chan_send(term, 'Hello\027]133;D\027\\\nworld!' .. ('\n'):rep(6))
+      screen:expect([[
+        world!                                            |
+        Hello                                             |
+        world!                                            |
+                                                          |*5
+        ^                                                  |
+        {5:-- TERMINAL --}                                    |
+      ]])
+      eq({ 25, 5 }, exec_lua('return _G.cursor'))
+
+      api.nvim_set_option_value('scrollback', 10, {})
+      eq(19, api.nvim_buf_line_count(0))
+
+      api.nvim_chan_send(term, 'Hello\nworld!\027]133;D\027\\')
+      screen:expect([[
+        Hello                                             |
+        world!                                            |
+                                                          |*5
+        Hello                                             |
+        world!^                                            |
+        {5:-- TERMINAL --}                                    |
+      ]])
+      eq({ 19, 6 }, exec_lua('return _G.cursor'))
+
+      api.nvim_chan_send(term, '\nHello\027]133;D\027\\\nworld!\n')
+      screen:expect([[
+                                                          |*4
+        Hello                                             |
+        world!                                            |
+        Hello                                             |
+        world!                                            |
+        ^                                                  |
+        {5:-- TERMINAL --}                                    |
+      ]])
+      eq({ 17, 5 }, exec_lua('return _G.cursor'))
+
+      api.nvim_chan_send(term, 'Hello\027]133;D\027\\\nworld!' .. ('\n'):rep(6))
+      screen:expect([[
+        world!                                            |
+        Hello                                             |
+        world!                                            |
+                                                          |*5
+        ^                                                  |
+        {5:-- TERMINAL --}                                    |
+      ]])
+      eq({ 12, 5 }, exec_lua('return _G.cursor'))
+
+      api.nvim_chan_send(term, 'Hello\027]133;D\027\\\nworld!' .. ('\n'):rep(8))
+      screen:expect([[
+        world!                                            |
+                                                          |*7
+        ^                                                  |
+        {5:-- TERMINAL --}                                    |
+      ]])
+      eq({ 10, 5 }, exec_lua('return _G.cursor'))
+
+      api.nvim_chan_send(term, 'Hello\027]133;D\027\\\nworld!' .. ('\n'):rep(20))
+      screen:expect([[
+                                                          |*8
+        ^                                                  |
+        {5:-- TERMINAL --}                                    |
+      ]])
+      eq({ -2, 5 }, exec_lua('return _G.cursor'))
     end)
 
     it('does not cause hang in vim.wait() #32753', function()